The source DESCRIPTION for this object is blank, so this reading is inferred from its name, syntax, and table position: it is a read-write weight (1-55) assigned per hardware queue (indexed by swL2QOSSchedulingClassIndex, one of the switch's four priority queues) alongside swL2QOSSchedulingMechanismCtrl, so it most likely configures the relative weight a queue gets under weighted round-robin (WRR) scheduling. An admin would raise this value on a queue carrying latency-sensitive traffic to give it more service opportunities relative to other queues.